The zebra mussel or Dreissena polymorph is a bivalve mollusk native to Europe. This organism has been unintentionally introduced into North American waters by the discharge of ballast water from transoceanic ships. Adult zebra mussels spread rapidly because the adults produce a free-floating reproductive stage called a veliger. Veligers are planktonic young that may drift in currents for up to 30 days. These larvae are abundant and small, and are able to pass through water intake pipe grates and infest the interior of the intake pipes. Often these intake pipes may be several miles long.
These mussels have already attached themselves to the submerged parts of municipal water systems, including intake pipes, which has greatly restricted the inflow of water to electrical generating and water treatment facilities, by reducing the diameter of the available water flow area inside the intake pipe. The zebra mussel is harmful to water systems, and are capable of colonizing on any firm substrate. Intake screens and pipes are especially good for mussel colonization due to the abundance of food near the intake pipe screens. Colonies form that may be over seven inches thick.
Current cleaning devices and methods require the municipality to cease use of the pipe for many months while the cleaning operation is carried out. Typical pipe cleaning operations use either pressurized fluids to propel and clean dirt or sludge in pipes, or use pipe pigs with rubber seals that conform to the inside of the pipe. However, such systems typically are limited to up to 48" diameter pipes and are very expensive to operate to remove this type of underwater aquatic infestation. Another problem is that municipalities can not afford to close off intake pipes for an extended period of time to allow for cleaning.
Consequently, there exists a need for an effective underwater pipe cleaning device that is capable of removing unwanted aquatic infestation such as zebra mussels without causing extended shut down of the use of the pipe. Furthermore, there exists a need for a cleaning device that may be inserted regardless of the extent of infestation in the pipe.